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{"Abstract":["Gulf Stream paths (daily, monthly, and annual) from 1993-01-01 to 2023-12-31 are identified via the longest 25-cm sea surface height contour in the Northwest Atlantic (75°W–55°W; 33°N–43°N) from the daily 1/8° resolution maps of absolute dynamic topography from the E.U. Copernicus Marine Service product Global Ocean Gridded Level 4 Sea Surface Heights and Derived Variables Reprocessed 1993 Ongoing, following the methodology of Andres (2016). The daily sea surface height fields are averaged to monthly and annual fields to identify the corresponding monthly and annual Gulf Stream paths. Additionally, an updated Gulf Stream destabilization point time series (1993–2023), which builds upon the work of Andres (2016), was generated using the E.U. Copernicus Marine Service product Global Ocean Gridded Level 4 Sea Surface Heights and Derived Variables Reprocessed 1993 Ongoing (1/8°). Similar to Andres (2016), the monthly Gulf Stream path is identified as the 25-cm SSH contour from absolute dynamic topography maps. The 12 monthly mean paths are divided yearly into 0.5° longitude bins (from 75°W to 55°W). In some months, the Gulf Stream can take a meandering path and contort over itself in an “S” curve. In these cases, the northernmost latitude is used in the variance calculation to resolve the issue of multiple latitudes for a single longitude. The variance of the Gulf Stream position (latitude) is then calculated for each year using the 12 monthly mean paths. The destabilization point is defined as the first downstream distance (longitude) at which the variance of the Gulf Stream position exceeds 0.4(°)2, which differs from the original threshold value of 0.5(°)2 in Andres (2016). The threshold value of 0.4(°)2 is the 70th percentile of variance for all years, which marks the transition from a relatively stable jet to an unstable, meandering current in the new higher-resolution (1/8°) maps of absolute dynamic topography.\n\nThanks to improvements in processing and combining satellite altimeter data (Taburet et al., 2019), in recent years the maps of absolute dynamic topography are different than the maps used by Andres (2016), which had 1/4° resolution. To account for the differences in the resolution of the data and corrections to the processing standards of altimeter data, a new threshold value was chosen that is consistent with the methods of Andres (2016), i.e., the threshold still signifies the transition between a stable and unstable Gulf Stream. However, a lower threshold value is necessary in the new absolute dynamic topography maps since finer-resolution data can separate distinct local maxima in variance, which could be smoothed together in coarser data, and may cause the destabilization point to be identified further downstream if the threshold were not adjusted. The 70th percentile of variance (0.4(°)2) for all years (1993–2023) was chosen as the threshold because the distribution of variance is right-skewed with a long tail and the 70th percentile separate lower variance associated with meridional shifts in the Gulf Stream path from the extreme, vigorous meadnering that occurs downstream of the "destabilization point".\n\nThe daily, monthly, annual Gulf Stream paths, and the updated destabilization point time series were generated using the E.U. Copernicus Marine Service product Global Ocean Gridded Level 4 Sea Surface Heights and Derived Variables Reprocessed 1993 Ongoing (https://doi.org/10.48670/moi-00148). \n\n \n\n "]} 

Biomass–fungi composite materials primarily consist of biomass particles (sourced from agricultural residues) and a network of fungal hyphae that bind the biomass particles together. These materials have potential applications across diverse industries, such as packaging, furniture, and construction. 3D printing offers a new approach to manufacturing parts using biomass–fungi composite materials, as an alternative to traditional molding-based methods. However, there are challenges in producing parts with desired quality (for example, geometric accuracy after printing and height shrinkage several days after printing) by using 3D printing-based methods. This paper introduces an innovative approach to enhance part quality by incorporating ionic crosslinking into the 3D printing-based methods. While ionic crosslinking has been explored in hydrogel-based bioprinting, its application in biomass–fungi composite materials has not been reported. Using sodium alginate (SA) as the hydrogel and calcium chloride as the crosslinking agent, this paper investigates their effects on quality (geometric accuracy and height shrinkage) of 3D printed samples and physiochemical characteristics (rheological, chemical, and texture properties) of biomass–fungi composite materials. Results show that increasing SA concentration led to significant improvements in both geometric accuracy and height shrinkage of 3D printed samples. Moreover, crosslinking exposure significantly enhanced hardness of the biomass–fungi mixture samples prepared for texture profile analysis, while the inclusion of SA notably improved cohesiveness and springiness of the biomass–fungi mixture samples. Furthermore, Fourier transform infrared spectroscopy confirms the occurrence of ionic crosslinking within 3D printed samples. Results from this study can be used as a reference for developing new biomass–fungi mixtures for 3D printing in the future.